Troubleshooting Image Conversion

Inappropriate ioctl for device

This error is somewhat mysterious, but in at least one case it was caused by the Netpbm tools using shared libraries instead of statically linked libraries. If this case applies to you, you may need to recompile Netpbm and tell it to use statically linked libraries:

Do you want libnetpbm to be statically linked or shared?
static or shared [shared] ==> static